Salience of Somatosensory Stimulus Modulating External-to-Internal Orienting Attention

Attachment Security Priming Delayed Negative Information-Related Attentional Disengagement Among Anxiously Attached Individuals: Evidence From Behavioral and Functional MRI Experiments

Although attachment security has been found to attenuate people’s experience of unpleasant information, how it modulates the attentional process toward such information remains unknown. The present study examined this issue by employing the dot-probe task in functional MRI. After completing the Experiences in Close Relationships-Revised questionnaire (ECR-R), 39 participants were asked to complete the dot-probe task in two conditions: the attachment security priming condition and neutral priming condition. The behavioral results revealed that individuals with high level of attachment anxiety exhibited larger attention disengagement from negative traits in the security priming condition than in the control condition. Correspondingly, the brain regions involved in attention regulation and shifting, such as the posterior cingulate and bilateral parietal area, were less activated among high anxiously attached individuals in the security priming condition. These results suggest a role of attachment security priming in regulating the emotional response in anxiously attached individuals during the attentional stage.

Reliability of measurements for sub-painful and painful perception on artificial electrical stimulations

Artificial electrical stimulation is a common type of stimulus to induce sub-painful and painful sensation in clinical or neuroscience experiments. The Numerical Rating Scale (NRS) is often used to evaluate subjective perception due to external stimulations. Yet the relationship between the intensity levels of electrical stimulations and self-perception has seldom been examined. The aim of the study was to obtain evidence on the reliability and accuracy of sub-painful and painful perceptions of healthy participants using the NRS under different levels of electrical stimulus. A total of 72 pain-free healthy volunteers (female=44) were recruited. In the first experiment, each participant was given different levels of a non-nociceptive or nociceptive electrical stimulus and then asked to give a perception rating based on an 11-point NRS. In the second experiment, each participant was asked to memorize 5 levels of sub-nociceptive or nociceptive stimuli and to recognize the level of stimulus given each time. For the NRS rating task, intraclass coefficients (ICCs) reached satisfactory level for sub-nociceptive (0.85<ICC<0.93) and nociceptive stimulation (0.90<ICC<0.96). The ICCs were the highest for the weakest sub-nociceptive and nociceptive stimuli. For the stimulus recognition task, accuracy was also found to be highest for the weakest sub-nociceptive stimulus (κ=0.67) and lowest for the strongest nociceptive stimulus (κ=0.34). The results suggest that, with adequate training, NRS can be a reliable measurement tool for both sub-painful and painful rating due to electrical stimulation.